System and method for endoluminal and translumenal therapy

ABSTRACT

A system for conducting denervation of the neural plexus adjacent the renal artery, comprises a pre-shaped ablative element operatively coupled to an elongate deployment member configured to be navigated into the renal artery, the pre-shaped ablative element comprising one or more RF electrodes disposed in an arcuate pattern; and an energy source operatively coupled to the one or more RF electrodes and being configured to cause current to flow from the pre-shaped ablative element and cause localized heating sufficient to denervate nearby neural tissue.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 13/355,321, now U.S. Patent Application Publication Number2012/0191083, filed on Jan. 20, 2012, entitled “SYSTEM AND METHOD FORENDOLUMINAL AND TRANSLUMENAL THERAPY,” which claims the benefit under 35U.S.C. §119 to U.S. Provisional Patent Application No. 61/434,797, filedJan. 20, 2011. The foregoing applications are hereby incorporated hereinby reference in their entirety

FIELD OF THE INVENTION

The invention relates generally to minimally invasive medicaltechniques, and more particularly to therapeutic denervation treatmentsusing endolumenal or translumenal instruments such aselectromechanically or robotically operated catheters.

BACKGROUND

Elongate medical instruments, such as catheters, are utilized in manytypes of medical interventions. Many such instruments are utilized inwhat have become known as “minimally invasive” diagnostic andinterventional procedures, wherein small percutaneous incisions ornatural orifices or utilized as entry points for instruments generallyhaving minimized cross sectional profiles, to mitigate tissue trauma andenable access to and through small tissue structures. One of thechallenges associated with minimizing the geometric constraints isretaining functionality and controllability. For example, some minimallyinvasive instruments designed to access the cavities of the bloodvessels and/or heart have steerable distal portions or steerable distaltips, but may be relatively challenging to navigate through tortuousvascular pathways with varied tissue structure terrain due to theirinherent compliance. Even smaller instruments, such as guidewires ordistal protection devices for certain vascular and other interventions,may be difficult to position due to their relatively minimal navigationdegrees of freedom from a proximal location, and the tortuous pathwaysthrough which operators attempt to navigate them. To provide additionalnavigation and operational functionality options for minimally invasiveinterventions, it is useful to have an instrument platform that may beremotely manipulated with precision, such as the robotic catheter systemavailable from Hansen Medical, Inc. under the tradename Sensei®. Theelongate instruments associated with such a system may be navigated notonly within the cardiovascular system, but also within other body lumensand cavities, such as those of the respiratory, gastrointestinal,urinary, and reproductive systems to address various maladies of thebody, including but not limited to various paradigms cardiovasculardisease. One such cardiovascular disease area of interest ishypertension, or high blood pressure, and it has been found that aspectsof hypertension may be controlled with denervation therapy of the nervesof the renal plexus adjacent the renal artery. It would be valuable tohave further interventional options than are presently available toaddress renal plexus denervation therapy.

SUMMARY

One embodiment is directed to a system for conducting denervation of theneural plexus adjacent the renal artery, comprising: a pre-shapedablative element operatively coupled to an elongate deployment memberconfigured to be navigated into the renal artery, the pre-shapedablative element comprising one or more RF electrodes disposed in anarcuate pattern; and an energy source operatively coupled to the one ormore RF electrodes and being configured to cause current to flow fromthe pre-shaped ablative element and cause localized heating sufficientto denervate nearby neural tissue. The arcuate pattern may comprise aj-curve. The j-curve may have a substantially constant radius ofcurvature. The arcuate pattern may comprise at least a portion of aspiral pattern. The arcuate pattern may comprise at least one fullhelical loop of a spiral pattern. The pre-shaped ablative element may besufficiently flexible such that it may be delivered to a locationadjacent to the subject neural tissue in a compressed form, before beingutilized to cause the localized heating in an expanded form. The systemfurther may comprise an atraumatic tip member coupled to a distal end ofthe pre-shaped ablative element and configured to prevent piercing oftissue structures near the subject neural tissue. The pre-shapedablative element may have an outer diameter configured to facilitatepullback of the pre-shaped ablative element while current is flowingfrom the pre-shaped ablative element, to cause an elongate lesion ofdenervation of nearby neural tissue. The elongate deployment member maycomprise an electromechanically steerable catheter. The system furthermay comprise a robotic instrument driver operatively coupled between theelectromechanically steerable catheter and a control computing system,the robotic instrument driver configured to move one or more controlelements of the electromechanically steerable catheter in response tosignals transmitted from the control computing system to causenavigation movement of the electromechanically steerable catheter.

Another embodiment is directed to a method for conducting a denervationprocess upon the neural plexus adjacent the renal artery, comprising:navigating a pre-shaped ablative element into the renal vein; imagingtargeted portions of the neural plexus from inside of the renal vein tocreate an anatomic map of the targeted portions; creating an electricalmapping of one or more neural strands comprising the targeted portions;and denervating the targeted portions by passing current through thepre-shaped ablative element while placing the pre-shaped ablativeelement in one or more desired configurations relative to the targetedportions, the configurations based at least in part upon the anatomicmap and electrical mapping. The pre-shaped ablative element may comprisean arcuate pattern. The arcuate pattern may comprise a j-curve. Thej-curve may have a substantially constant radius of curvature. Thearcuate pattern may comprise at least a portion of a spiral pattern. Thearcuate pattern may comprise at least one full helical loop of a spiralpattern. The pre-shaped ablative element may be sufficiently flexiblesuch that it may be delivered to a location adjacent to the subjectneural tissue in a compressed form, before being utilized to cause thelocalized heating in an expanded form. The method further may comprisetransforming the pre-shaped ablative element from a compressed form toan expanded form in situ before denervating the targeted portions. Themethod further may comprise moving the pre-shaped ablative elementrelative to the targeted portions while passing current through thepre-shaped ablative element to cause an elongate lesion of denervationof nearby neural tissue. Moving may be actuated by manual orelectromechanical pullback of the pre-shaped ablative element.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates certain aspects of renal vascular and neuroanatomy.

FIG. 2 illustrates a close-up view of a portion of a renal artery aswell as certain portions of an associated renal nerve plexus.

FIG. 3 illustrates a robotic catheter system configured for conductingminimally invasive medical interventions.

FIG. 4 illustrates an instrument driver and instrument assembly of arobotic catheter system configured for conducting minimally invasivemedical interventions.

FIGS. 5A-5D illustrate various aspects of an instrumentation system forconducting a trans-lumenal renal plexus denervation procedure with oneor more controllably steerable instruments and one or more controllablyexpandable members.

FIGS. 6A-6B illustrate various aspects of a trans-ureteral renal nerveplexus intervention utilizing the subject remotely steerable instrumentsystem.

FIG. 7 depicts a close up partial view of renal, cardiovascular, andassociated neuroanatomy in the abdomen adjacent the kidney.

FIG. 8 illustrates various aspects of a trans-ureteral renal plexusdenervation intervention.

FIG. 9 illustrates various aspects of a trans-arterial renal plexusdenervation intervention wherein instrumentation is taken across aportion of a wall of the celiac trunk artery.

FIG. 10 illustrates various aspects of a trans-arterial renal plexusdenervation intervention wherein instrumentation is taken across aportion of a wall of the superior mesentary artery.

FIG. 11 illustrates various aspects of a trans-venous renal plexusdenervation intervention wherein instrumentation is taken across aportion of a wall of the vena cava.

FIG. 12 illustrates various aspects of a trans-venous renal plexusdenervation intervention wherein instrumentation is taken across aportion of a wall of the renal vein.

FIG. 13 illustrates various aspects of a process for creating atrans-lumenal access port from inside of a subject tissue lumen orstructure, utilizing the access port for a diagnostic or interventionalprocedure, and closing the access port from inside of the subject tissuelumen.

FIGS. 14A-14H illustrate various aspects of a system for renalneuroplexus diagnostics and intervention in accordance with the presentinvention.

FIGS. 15A-15D illustrate various aspects of a system for renalneuroplexus diagnostics and intervention in accordance with the presentinvention, wherein OCT imaging techniques may be employed.

FIGS. 16-21 illustrate process embodiments in accordance with thepresent invention.

FIG. 22 illustrates an embodiment wherein a longitudinally displacedpattern may be used in a denervation treatment.

FIGS. 23A-23C illustrate an embodiment wherein a pullback technique maybe utilized in a denervation treatment with a pre-shaped spiralinstrument.

FIG. 24 illustrates an embodiment wherein an evacuated volume may beutilized to assist with a denervation treatment wherein an expandabledevice comprising one of more circuit elements is utilized in adenervation treatment.

FIGS. 25A and 25B illustrate embodiments wherein two or more guideinstrument assemblies may be utilized to conduct a denervationtreatment.

FIGS. 26A-26C illustrate an embodiment wherein a pullback technique maybe utilized in a denervation treatment with a pre-shaped J-curveinstrument.

FIGS. 27A-27C illustrate various aspects of manufacturing and behaviordetails of a pre-shaped spiral instrument embodiment.

FIGS. 28A and 28B illustrate various details of a pre-shaped J-curveinstrument embodiment.

FIGS. 29-34 illustrate process embodiments in accordance with thepresent invention.

DETAILED DESCRIPTION

Referring to FIG. 1, the kidneys (2) are shown in relation to the aorta(4), vena cava (6), ureters (8), renal veins (12) and portions of theneural anatomy of the renal plexus (14), which is coupled to the renalarteries (10). Referring to FIG. 2, a close-up orthogonal view of aportion of a renal artery (10) is shown, with bands of contractilesmooth muscle tissue (18) surrounding the longitudinal axis (16)circumferentially, and with strands of renal nerves (20) coupled to therenal artery (10), generally longitudinally along the renal artery (10).These strands of renal nerves (20) comprise the renal nerve plexus, orrenal plexus, which may be embedded within the adventitia of the renalartery (10). This nerve plexus extends along the renal artery until itjoins the parenchyma of the kidney (2). As briefly described above,hypertension and other diseases such as heart failure and chronic kidneydisease are a few of the disease states that result from chronicactivation of the sympathetic nervous system, especially the renalsympathetic nervous system, which comprises the renal plexus. Chronicactivation of the sympathetic nervous system is a maladaptive responsethat drives the progression of these disease states. Indeed, the renalsympathetic nervous system has been identified as a major contributor tothe complex pathophysiology of hypertension, various states of volumeoverload (such as congestive heart failure), and progressive heartdisease, in experimental and clinical research studies. Given theknowledge that hypertension is commonly neurogenic, there are newclinical intervention paradigms evolving whereby an attempt is made tolocate and ablate strands of renal nerves (20) comprising the renalplexus from the inside of the renal artery, via an endovascularapproach. Various challenges are presented with such an approach,including locating and appropriately denervating the nerve strandswithout damaging or necrosing the tissue of the renal artery wall. Ininvestigating extravascular approaches (i.e., approaching the renalplexus from outside of the walls of the renal artery), it has beendetermined that one of the key challenges is controllably navigating andoperating an instrument to a retroperitoneal location whereby the renalplexus may be more directly denervated via radiofrequency ablation orother techniques. An electromechanically, or “robotically”, operatedelongate instrument control system provides important functionality forsuch a challenge.

Referring to FIG. 3, a robotic catheter system is depicted having anoperator workstation (210) comprising a master input device (206),control button console (208), and a display (204) for the operator (202)to engage. In the depicted embodiment, a controller or control computerconfigured to operate the various aspects of the system is also locatednear the operator (202). The controller (212) comprises an electronicinterface, or bus (248), configured to operatively couple the controller(212) with other components, such as an electromechanical instrumentdriver (164), RF generator (214), localization system (216), or fiberbragg shape sensing and/or localization system (218), generally viaelectronic leads (232, 230, 236, 234, 240, 238, 242, 244, 246, 226).Electromechanically or robotically controlled catheter systems similarto that depicted in FIG. 3 are available from Hansen Medical, Inc. underthe tradename Sensei®, and described, for example, in U.S. patentapplication Ser. Nos. 11/481,433, 11/073,363, 11/678,001(“Intellisense”) and Ser. No. 11/637,951, each of which is incorporatedby reference in its entirety. In the depicted embodiment, the controller(212) preferably is operatively coupled (232) to the RF generator (214)and configured to control outputs of the RF generator (214), which maybe dispatched via electronic lead (230) to the disposable instrumentassembly (166). Similarly, the controller (212) preferably isoperatively coupled (236) to a localization system, such as anelectromagnetic or potential difference based localization system (216),such as those available under the tradenames CartoXP® and EnSite® fromBiosense Webster, Inc., and St. Jude Medical, Inc., respectively. Thelocalization system (216) preferably is operatively coupled via one ormore leads (234) to the instrument assembly (166), and is configured todetermine the three dimensional spatial position, and in certainembodiments orientation, of one or more sensors coupled to a distalportion of the instrument assembly relative to a coordinate systemrelevant to the controller and operator, such as a world coordinatesystem. Such position and/or orientation information may be communicatedback to the controller (212) via the depicted electronic lead (236) orother signal communication configuration such as a wireless datacommunication system (not shown), to enable the controller (212) andoperator (202) to understand where the distal portion of the instrumentassembly (166) is in space—for control and safety purposes. Similarly, afiber opticlocalization and/or shape sensing system (218) may be coupledbetween the controller (212) and instrument assembly (166) to assistwith the determination of position and shape of portions of theinstrument assembly, thermal sensing, contact sensing, and load sensing,as described, for example, in the aforementioned incorporated patentapplications.

Various types of shape sensing fibers may be used in the fiber opticlocalization and/or shape sensing system (218). It is well known that byapplying the Bragg equation (wavelength=2*d*sin(theta)) to detectwavelength changes in reflected light, elongation in a diffractiongrating pattern positioned longitudinally along a fiber or otherelongate structure maybe be determined. Further, with knowledge ofthermal expansion properties of fibers or other structures which carry adiffraction grating pattern, temperature readings at the site of thediffraction grating may be calculated. “Fiberoptic Bragg grating”(“FBG”) sensors or components thereof, available from suppliers such asLuna Innovations, Inc., of Blacksburg, Va., Micron Optics, Inc., ofAtlanta, Ga., LxSix Photonics, Inc., of Quebec, Canada, and IbsenPhotonics AIS, of Denmark, have been used in various applications tomeasure strain in structures such as highway bridges and aircraft wings,and temperatures in structures such as supply cabinets.

The use of such technology in shapeable instruments is disclosed incommonly assigned U.S. patent application Ser. Nos. 11/690,116;11/176,598; 12/012,795; 12/106,254; 12/507,727; 12/192,033; 12/236,478;and 12/837,440. The entirety of each of the above applications isincorporated by reference herein.

In an alternative variation, a single mode optical fiber is drawn withslight imperfections that result in index of refraction variations alongthe fiber core. These variations result in a small amount of backscatterthat is called Rayleigh scatter. Changes in strain or temperature of theoptical fiber cause changes to the effective length of the opticalfiber. This change in the effective length results in variation orchange of the spatial position of the Rayleigh scatter points. Crosscorrelation techniques can measure this change in the Rayleighscattering and can extract information regarding the strain. Thesetechniques can include using optical frequency domain reflectometertechniques in a manner that is very similar to that associated with lowreflectivity fiber gratings. A more complete discussion of these methodscan be found in M. Froggatt and J. Moore, “High-spatial-resolutiondistributed strain measurement in optical fiber with Rayleigh scatter”,Applied Optics, Vol. 37, p. 1735, 1998 the entirety of which isincorporated by reference herein.

Methods and devices for calculating birefringence in an optical fiberbased on Rayleigh scatter as well as apparatus and methods for measuringstrain in an optical fiber using the spectral shift of Rayleigh scattercan be found in PCT Publication No. W02006099056 filed on Mar. 9, 2006and U.S. Pat. No. 6,545,760 filed on Mar. 24, 2000 both of which areincorporated by reference herein. Birefringence can be used to measureaxial strain and/or temperature in a waveguide. Using Rayleigh scatterto determine birefringence rather than Bragg gratings offers severaladvantages. First, the cost of using Rayleigh scatter measurement isless than when using Bragg gratings. Rayleigh scatter measurementpermits birefringence measurements at every location in the fiber, notjust at predetermined locations. Since Bragg gratings require insertionat specific measurement points along a fiber, measurement of Rayleighscatter allows for many more measurement points. Also, the process ofphysically “writing” a Bragg grating into an optical fiber can be timeconsuming as well as compromises the strength and integrity of thefiber. Such drawbacks do not occur when using Rayleigh scattermeasurement.

In one embodiment, an optical fiber sensor (238), which may or may notinclude Bragg gratings, may be positioned between the distal tip of oneor more instruments in the assembly and coupled proximally to theoptical fiber sensor interrogator (218) in a manner described in U.S.Provisional Patent application No. 61/513,488 the entirety of which isincorporated by reference herein, and outputs from such system may beelectronically communicated (240) to the controller (212) to facilitatecontrol and safety features, such as closed loop shape control of one ormore portions of the instrument assembly, as described, for example, inthe aforementioned incorporated references. A feedback and control lead(226) is utilized to operatively couple the instrument driver (164) tothe controller. This lead (226) carries control signals from thecontroller (212) to various components comprising the instrument driver(164), such as electric motors, and carries control signals from thevarious components of the instrument driver (164), such as encoder andother sensor signals, to the controller (212). The instrument driver(164) is coupled to the operating table (222) by a setup structure (220)which may be a simple structural member, as depicted, or a morecomplicated movable assembly, as described in the aforementionedincorporated references. A bus configuration (248) couples the variousdepicted leads (226, 246, 244, 242, 240, 236, 232) with the controller(212). Alternatively, wireless configurations may be utilized.

Referring to FIG. 4, an orthogonal view of an instrument driver (164)and instrument assembly (166) is depicted, this configuration having theability to monitor loads applied to working members or tools placedthrough a working lumen defined by the instrument assembly (166). Inthis embodiment, such loads are determined with load sensors (168)located within the housing of the instrument driver, as described in theaforementioned incorporated references. In other embodiments, loadsimparted to various tools or aspects of the instrument assembly (166)may be monitored using load sensors or components thereof which areembedded within or coupled to distal portions (170) of such tools orinstrument assembly portions.

Referring to FIGS. 5A-5D, various closer views of aspects of instrumentembodiments in accordance with the present invention are shown.Referring to FIG. 5A, a steerable sheath instrument (22) is depictedhaving a proximal interface (shown in the aforementioned incorporated byreference disclosures in reference to robotic sheath instrumentembodiments) configured to be removably and driveably coupled to aninstrument driver (164) such as that depicted in FIG. 4. The distalportion of the sheath instrument (22) comprises an expandable membersuch as a balloon, which may be controllably expanded via an inflationlumen (42), as shown in the detail view of FIG. 5B. Also shown in FIGS.5A and 5B is an elongate steerable guide instrument (24) which may beproximally coaxially positioned through a guide insertion lumen (44)defined into the sheath instrument (22), and distally directed outthrough a side port formed through the balloon member (26), after beingrouted through an arcuate portion (46) of the guide insertion lumen(44). With the balloon member (26) in an inflated or deflated state, thedepicted instrument assembly may be placed through a lumen and utilizedto create a side port across the wall of the lumen. In one embodiment, aneedle may initially be advanced through the sheath instrument lumen(44, 46) and across the subject tissue wall, followed by a dilatorinstrument and/or guidewire, which may be followed by the guideinstrument (24) in an over-the-wire type technique using a working lumendefined into the guide instrument (24). As shown in FIGS. 5A and 5B, thedistal portion of the elongate guide instrument (24) may be outfittedwith one or more ultrasound transducers (28), one or more localizationsensors (30), and one or more treatment elements (such as aradiofrequency electrode, a cryoablation reservoir, a high intensityfocused ultrasound treatment transducer, a laser or other radiationemitter, or the like 32) which may be utilized to denervate nervestrands, such as those of the renal plexus. In another embodiment, thedistal portion of the guide instrument (24) may be operatively coupledto an antenna, such as a microwave antenna, to sense reflectedradiation, such as blackbody radiation, which may be correlated to thetemperature of nearby tissues, as described, for example, in U.S. patentapplication Ser. No. 12/833,927, which is incorporated by referenceherein in its entirety. Such an embodiment allows for direct sensing ofthermal conditions in nearby tissue structures of interest—as opposed toother competing techniques such as thermocouples placed adjacent RFheating electrodes, which are more aptly configured to read thetemperature of the electrodes rather than nearby tissues.

Referring to the close-up view of FIG. 5B, the side port of the balloonmember (26) comprises a lumen port closure configuration having one ormore closure clip elements (34) constrained in an open configuration bythe geometry of the balloon member (26) to which it is coupled. Uponcontrollable inflation of a small clip deployment bladder (38) coupledto the balloon member (26) using an inflation lumen (40), the clip (34)may be advanced outward, and small barb-like fastening members (36)configured to fasten to nearby tissue structures upon exposure and mildadvancement load from the deployment bladder (38) and/or balloon member(26) inflation will engage nearby tissue structures, while the clip (34)simultaneously will become unconstrained from its coupling with thestructure of the balloon member (26) and will be free to resume anunloaded configuration, preferably configured to coapt the tissue aroundthe circumference of the access port toward itself. Suitable clips madefrom bioinert metals such as nitinol are available from MedtronicCorporation and were invented by Coalescent Surgical, Inc. and clearedby the FDA for a different medical application (closure of vascularanastomosis). The fastening features (36) may be sintered onto theclips, welded, coupled with a preferably bioinert adhesive, or formed oretched into the same structure that comprises the fastening element(36). Referring ahead to FIG. 13, a process for utilizing aconfiguration such as that depicted in FIGS. 5A and 5B to create andsubsequently close a lumen side port is illustrated.

Referring to FIG. 13, after positioning an expandable balloon member ina contracted form to a desired insertion location and orientation (i.e.,roll orientation relative to the longitudinal axis commonly associatedwith a lumen) (148), the expandable balloon member maybe controllablyinflated to substantially occlude the body lumen (with the exception offlow which may be facilitated through a working through-lumen of asubject sheath instrument) and create a relatively low-level hooptension in portions of the body lumen adjacent to the expanded balloonmember (150). An elongate diagnostic and/or interventional instrumentmay then be advanced out of a side port of the expandable balloon member(in one embodiment, as described above, in an over-the-needle, wire, ordilator configuration), creating a trans-lumenal access port (152).Using this access port, a diagnostic and/or interventional procedure maybe conducted translumenally with one or more elongate instruments (154).When the interventional procedure has been completed, the elongateinstruments may be refracted (156) and a controlled closure of thetranslumenal access port executed by urging the one or more closureclips away from a housing depression formed in the balloon member, andinto at least a portion of the tissue structure adjacent thetranslumenal access port, with the one or more clips maintaining theirconstrained (i.e., constrained until they are uncoupled from the balloonmember housing interface) configurations as they are fastened to thenearby tissue (158). A bladder and associated pressure control lumen, asshown in FIG. 5B, for example, may be utilized to controllably advancethe one or more clips outward, as described above. With the one or moreclosure clips fastened to the subject tissue structure, preferably in apattern about the annulus of the translumenal access port, incrementalpressure in the bladder or other mechanism may be utilized to uncouplethe one or more closure clips from the balloon member, allowing them toassume an unloaded configuration preferably selected to cause tissuecoaptation about the previous location of the translumenal access portto urge the port closed (160). With the port closed, the instruments maybe withdrawn (162).

Referring back to FIG. 5C, an embodiment similar to that of FIG. 5B isdepicted, with the exception that an elongate treatment probe (58), suchas a bendable or steerable needle, comprising a series plurality (59) ofdistally-located treatment elements (akin to element 32) coupled to ahelically shaped (48) treatment probe distal portion that is configuredto be inserted and/or wrapped around a given tissue structure fordiscrete, controlled ablation of such tissue structure. The helicalshape (48) is selected to minimize the risk of stenosis bylongitudinally stretching out a circumferential lesion (i.e., anon-stretched purely circumferential lesion may have scar tissueexpansion inward from directly opposing tissue structure portions,leaving it more vulnerable to stenosis by such scarring; the helicalpitch shape 48 is configured to avoid this). An orthogonal view isdepicted in FIG. 5D.

Referring to FIGS. 6A, 6B, and 8, a trans-ureteral renal nerve plexusdenervation procedure is illustrated. As shown in FIG. 6A, a guide andsheath instrument assembly similar to that depicted in FIGS. 5A and 5Bmay be inserted through the urethra (52) and into the bladder (50) whereit may be navigated to cannulate one of the ureters (8) and be directedtoward the kidney (2), as shown in FIG. 6B. Referring to FIG. 6B, withthe sheath instrument (22) desirably located and oriented relative tothe renal artery (10) (confirmation of which may be assisted usingultrasound, fluoroscopy, and other imaging modalities), a transcutaneousaccess port may be created through an expanded balloon member (26) toprovide an elongate guide instrument, such as a robotically steerableguide instrument (24) with relatively immediate retroperitoneal accessto the outside of the renal artery, and therefore the renal plexus. Suchaccess may be utilized to directly ablate and/or otherwise denervateselected portions of the renal plexus. A similar configuration may beutilized to conduct a trans-lumenal diagnostic and/or interventionalprocedure via various other anatomical situations. For example, in anembodiment similar to that described in reference to FIGS. 5A-5D and6A-6B, an elongate steerable instrument configuration may be utilized tomove through the lower gastrointestinal tract, up into the intestine,and be utilized to cross the intestine closely adjacent the renal plexusto conduct a similar denervation procedure from a different anatomicplatform. One or more stents or stentlike members may be left behind tobolster or replace the closure provided by the clip-like elements (34),and such stent or stentlike member may be subsequently removed, asdirected by the physician, in a manner similar to that conducted incertain conventional ureter wound closure scenarios.

Referring to FIG. 8, a process flow for such a procedure is illustrated.With a sheath instrument advanced across a urethra and into the bladder(60), steerability and navigation capabilities of the sheath instrumentmay be utilized to cannulate a ureter (potentially using anover-the-wire technique) (62). The distal portion of the sheathinstrument may be advanced into an optimal position and orientation foraccessing the retroperitoneal space adjacent the renal artery and renalplexus (64). A balloon member may be expanded into a guide instrumentdeployment configuration wherein ureter portions adjacent the balloonare slightly tensioned in an expansive manner from the ballooninflation; the kidneys may continue to drain using a lumen definedthrough at least a portion of the balloon and/or sheath member (68). Aguide member may be advanced out of a side port formed in the balloonmember to create a translumenal access port (in some embodimentsutilizing over the wire or over the needle techniques) (70). With thetranslumenal access created, the guide instrument may be advanced towardthe desired neuroanatomy (72) from the outside of the renal artery, andcontrolled denervation accomplished using radiofrequency energy emissionor other denervation modalities, as described above (74). Subsequently,the instrumentation may be retracted, the access port closed (forexample, as described above), the balloon deflated, and normal functionreturned without the endolumenal instrumentation in place (76).

Referring to FIG. 7, various aspects of the cardiovascular andneurological anatomy around the renal system are depicted to illustratethat there are several translumenal access opportunities to theretroperitoneal region of the renal plexus, including but not limited tothe vena cava (6), the renal veins (12), the celiac trunk artery (54),and the superior mesentery artery (56). Referring to FIG. 9, a processfor implementing a translumenal renal plexus denervation with atrans-celiac approach is illustrated. A sheath instrument is advanced upthe aorta and into the celiac trunk artery (78). An over the wireprocess may be utilized to gain full access to the celiac trunk for thedistal portion of the sheath instrument (80). The distal portion of thesheath may be adjusted in position and orientation to optimize atranslumenal approach toward the renal plexus (82). A balloon membercoupled to the distal portion of the sheath member may be expanded toslightly tension the celiac trunk portions adjacent the balloon member,and blood may continue to flow past the balloon member using a lumenformed through the balloon member (86). A guide instrument may beadvanced out of a side port of the sheath instrument to create atransvascular access port (88). In one embodiment, a sharpened needlemay be utilized for the initial advancement, followed by the guideinstrument in an over the needle interfacing relationship. The distalportion of the guide instrument may be positioned adjacent the renalplexus (90), and one or more RF electrodes may be utilized tocontrollably denervate portions of the renal plexus (92). Subsequentlythe guide instrument may be retracted, the transvascular access portclosed (for example, using one or more clip members as described abovein reference to FIG. 5B), the sheath balloon member deflated, and thesheath instrument retracted to leave a complete closure (94).

Referring to FIG. 10, a process for implementing a translumenal renalplexus denervation with a trans-mesentary approach is illustrated. Asheath instrument is advanced up the aorta and into the superiormesentary artery (96). An over the wire process may be utilized to gainfull access to the celiac trunk for the distal portion of the sheathinstrument (98). The distal portion of the sheath may be adjusted inposition and orientation to optimize a translumenal approach toward therenal plexus (100). A balloon member coupled to the distal portion ofthe sheath member may be expanded to slightly tension the superiormesentery artery portions adjacent the balloon member, and blood maycontinue to flow past the balloon member using a lumen formed throughthe balloon member (104). A guide instrument may be advanced out of aside port of the sheath instrument to create a transvascular access port(106). In one embodiment, a sharpened needle may be utilized for theinitial advancement, followed by the guide instrument in an over theneedle interfacing relationship. The distal portion of the guideinstrument may be positioned adjacent the renal plexus (108), and one ormore RF electrodes may be utilized to controllably denervate portions ofthe renal plexus (110). Subsequently the guide instrument may beretracted, the transvascular access port closed (for example, using oneor more clip members as described above in reference to FIG. 5B), thesheath balloon member deflated, and the sheath instrument retracted toleave a complete closure (112).

Referring to FIG. 11, a process for implementing a translumenal renalplexus denervation with a trans-vena-cava approach is illustrated. Asheath instrument is advanced up into the vena cava from a femoral orother access point (114). The distal portion of the sheath may beadjusted in position and orientation to optimize balloon memberpositioning for a translumenal approach toward the renal plexus (116). Aballoon member coupled to the distal portion of the sheath member may beexpanded to slightly tension the celiac trunk portions adjacent theballoon member, and blood may continue to flow past the balloon memberusing a lumen formed through the balloon member (120). A guideinstrument may be advanced out of a side port of the sheath instrumentto create a transvascular access port (122). In one embodiment, asharpened needle may be utilized for the initial advancement, followedby the guide instrument in an over the needle interfacing relationship.The distal portion of the guide instrument may be positioned adjacentthe renal plexus (124), and one or more RF electrodes may be utilized tocontrollably denervate portions of the renal plexus (126). Subsequentlythe guide instrument may be retracted, the transvascular access portclosed (for example, using one or more clip members as described abovein reference to FIG. 5B), the sheath balloon member deflated, and thesheath instrument retracted to leave a complete closure (128).

Referring to FIG. 12, a process for implementing a translumenal renalplexus denervation with a renal vein approach is illustrated. A sheathinstrument is advanced up the vena cava and into the renal vein (130).An over the wire process may be utilized to gain full access to therenal vein for the distal portion of the sheath instrument (132). Thedistal portion of the sheath may be adjusted in position and orientationto optimize a translumenal approach toward the renal plexus (134). Aballoon member coupled to the distal portion of the sheath member may beexpanded to slightly tension the celiac trunk portions adjacent theballoon member, and blood may continue to flow past the balloon memberusing a lumen formed through the balloon member (138). A guideinstrument may be advanced out of a side port of the sheath instrumentto create a transvascular access port (140). In one embodiment, asharpened needle may be utilized for the initial advancement, followedby the guide instrument in an over the needle interfacing relationship.The distal portion of the guide instrument may be positioned adjacentthe renal plexus (142), and one or more RF electrodes may be utilized tocontrollably denervate portions of the renal plexus (144). Subsequentlythe guide instrument may be retracted, the transvascular access portclosed (for example, using one or more clip members as described abovein reference to FIG. 5B), the sheath balloon member deflated, and thesheath instrument retracted to leave a complete closure (146).

Referring to FIGS. 14A-14G, various aspects of configurations selectedto controllably denervate portions of a renal plexus or fibers thereofare illustrated. As shown in FIG. 14A, a robotic sheath instrument (22)and guide instrument (24) assembly is depicted being advanced up theaorta (4) and into the renal artery (10). The coaxial slidable couplingof the two robotic instruments is useful in the depicted embodiment fortelescoping the smaller instrument relative to the larger, as depictedin FIGS. 14B and 14C, for example. In another embodiment, a singlerobotic guide type instrument may be utilized without the load-shieldingand related fine-control benefits of having a “home base” sheathstructure (22) positioned at the aorta (4) as shown, for example, inFIGS. 14B and 14C. In another embodiment, a non-robotic sheath may beutilized along with a robotic guide instrument (24). In yet anotherembodiment, two non-robotic instruments may be utilized, such assteerable catheters or sheaths that are responsive tonon-electromechanical pullwire or pushwire loading for steerability.

Referring again to FIG. 14A, several nerve tissue strands (20) aredepicted surrounding portions of the renal artery (10), as are groups ofjuxtaglomerular apparatus (or “JGA”) cells (198), which are known to beresponsible, at least in part, for the production of renin in responseto efferent neural signals through the fibers (20) of the renal plexus,and thereby correlated with increases in blood pressure. Also shown areseveral arterioles (196) where the renal artery (4) branches down tomeet the kidney.

Referring to FIG. 14B, the larger sheath instrument (22) is positionedat the mouth of the renal artery (10) while the smaller guide instrument(24) preferably is electromechanically advanced, and navigated to avoidlocal tissue trauma. As described above in reference to FIGS. 5A-5D, thedistal portion of the guide instrument (24) may be equipped with varioussensors (i.e., such as ultrasound transducers, localization sensors,thermocouples, and/or radiation antennae such as microwave antennae forblackbody radiation sensing) and/or treatment elements (i.e., such ashigh intensity focused ultrasound transducers, RF electrodes, laseremission elements, fluid emission elements, and the like). Referring toFIG. 14C, further insertion of the guide instrument (24) into the renalartery is facilitated by the electromechanical control of a roboticcatheter system, the navigation of which may be facilitated by imagingmodalities such as transcutaneous ultrasound, transvascular ultrasound,intravascular ultrasound, fluoroscopy, and navigation within aregistered three-dimensional virtual environment created using imagesfrom modalities such as computed tomography, 3-dimensional computedtomography, magnetic resonance, X-ray, fluoroscopy, and the like, asdescribed, for example, in the aforementioned incorporated references.For example, in one embodiment, a “no touch” insertion may beaccomplished utilizing the stability provided by the placement of thesheath instrument (22), along with the navigability of a registered andreal-time (or near real-time) imaged robotically steerable guideinstrument (24).

Referring to FIG. 14D, subsequent to cannulation of the renal artery(10) to a position approximately adjacent the renal arterioles (196), abrief mapping study or investigation may be executed. This mapping studymay be preceded by preoperative or intraoperative imaging to determineat least some information regarding the positions, or likely positions,of aspects of the renal plexus. Referring again to FIG. 14D, in oneembodiment, a flexible, expandable device (292), such as a controllablyexpandable balloon or stentlike structure, may be controllably deployedfrom the guide instrument (24) and expanded to provide a directinterface between the tissues of the subject lumen and circuit elements(294) of the expandable device (292), the circuit elements beingconfigured to detect nearby electrical signals, and in one embodiment tobe alternatively be utilized to treat the nearby tissues through thecontrollable flow of current therethrough. In one embodiment, aconformal electronics polymer material, such as that available under thetradename MC10® by MC10 Corporation of Cambridge, Mass., may be utilizedto embed radiofrequency (“RF”) or other electrode circuitry within aninflatable or expandable substrate, as depicted in FIGS. 14D and 14E.Referring to the close up view of FIG. 14F, the circuit elements (294)may have sharpened probing portions (296) configured to protrude intonearby tissues, such as the walls of the renal artery (4), to gaincloser proximity to signals passing through nearby neural structures,such as the depicted renal plexus fibers (20), and/or to gain closerproximity to structures to be denervated or altered in a treatmentphase, such as by applying RF energy for selective denervation byheating. Full inflation or expansion of the associated expandable device(292) may be required to seat the probing portions (296) across portionsof the nearby tissue structures, and the assembly of the expandabledevice (292), circuit elements (294), and probing portions (296)preferably is configured to be retractable back into the deliveryinstrument (24) without damage to nearby structures. In the embodimentdepicted in FIGS. 14D-14F, deflation or controlled outer geometryshrinking of the expandable device (292), concomitant with incrementalinsertion of the guide instrument (24) and slight refraction of theexpandable device (292), may be utilized to safely retract theexpandable device after mapping and/or treatment.

Referring to FIG. 14G, in another embodiment, an individual probe member(298), such as an RF needle tip, may be utilized to selectively probepertinent tissue structures for both mapping and treatment steps.Preferably the controller of the robotic catheter system is configuredto not only controllably navigate the probe member (298) to locations ofinterest with a desirable insertion vector and insertion location, butalso to store trajectory, path, location, and other informationpertinent to each diagnostic and/or treatment step for constantmonitoring of the procedure, and also ease of repeatability—or ease ofavoiding repeatability (i.e., in scenarios wherein it is not desirableto conduct two RF heating bouts on the same tiny volume of tissue).

Referring to FIG. 14H, in one embodiment, a probe member (298) may benavigated directly to discrete JGA cells (198) or lesions of JGA cellsto selectively destroy these directly. Any of the embodiments describedherein may incorporate load sensing capabilities of the subject roboticcatheter system, along with haptic input device features, to facilitatefine, atraumatic, predictable navigation of the diagnostic and/ortreatment tools.

Referring to FIG. 15A, in another embodiment, an optical coherencetomography (or “OCT”) fiber (300) may be coupled between a distal lens(302) and a proximal emitter/interferometer (not shown; available fromsources such as ThorLabs, Inc., of Newton, N.J.) to facilitate OCTtissue structure threshold sensing (i.e., the sensing and/orvisualization of boundaries of nearby tissue structures, such as therenal artery (10) wall thresholds, nerve fiber 20 structure thresholds,and the like) with a virtual field of view (304) dependent upon the lens(302) and emissions parameters. Such OCT imaging analysis may beutilized not only to locate structures of interest, but also to treatsuch structures—with near-real-time analysis of not only the tissuestructure thresholds, but also thresholds of other objects, such as RFelectrode probe tips and the like. The embodiment of FIG. 15A featuresan OCT configuration wherein the lens (302) is located on a distal faceof the guide instrument (24). Referring to FIG. 15B, an arcuateconfiguration of the OCT fiber (300) proximal to the side-oriented lens(302) and field of view (304) may be utilized for a side-capturingconfiguration. Referring to FIG. 15C, another side-capturingconfiguration is facilitated by a mirror or reflector (306) configuredto reflect outgoing and incoming light signals as shown.

Referring to FIG. 15D, an embodiment is shown wherein a working volume(318) is evacuated of blood to facilitate greater flexibility withlight-based imaging technologies, such as video and OCT. In other words,the embodiments of FIGS. 15A-15C showed the lens (302) purposefully inalmost direct opposition to nearby tissue structures, to avoidscattering and other effects of red blood cells and other elements offlowing blood which may negatively impact such imaging. The embodimentof FIG. 15D addresses this concern by temporarily (i.e., for a shortperiod of time, as dictated by the pathophysiology of the associatedkidney and other tissue structures) evacuating the working volume (318)of blood. This is accomplished in the depicted embodiment by inflatingtwo expandable occlusive elements (308, 310), such as balloons, andevacuating the captured blood using simple vacuum proximally through thesheath (22) and associated instruments. A larger delivery member (314)accommodates coupling of the guide instrument (24) and also the volumecapture assembly, which comprises the two expandable occlusive elements(308, 310) and a coupling member (312). A guide instrument port (316)allows for slidable coupling of the proximal expandable occlusiveelement (310) and the guide instrument (24). With such a configuration,various imaging devices may be utilized to create images of nearbyanatomy, such as ultrasound (in which case a transmissive medium, suchas saline, may be pumped into the working volume for sound wavetransmission enhancement and subsequently removed), CCD cameras, CMOScameras, fiberscopes, and the like, in addition to the aforementionedimaging configurations such as OCT.

Referring to FIGS. 16-21, various process embodiments are illustratedwherein one or more minimally invasive instruments may be utilized indiagnostic and/or interventional medical procedures. Referring to FIG.16, after a remotely steerable sheath catheter instrument is insertedinto the aorta and navigated toward the renal artery (175), the renalartery may be cannulated, for example with a coaxially associatedremotely steerable guide instrument that is movably coupled to thesheath instrument (174). An interactive imaging study, or steps thereof,may be conducted of the renal artery and associated neural anatomy usingone or more minimally invasive imaging modalities, such as ultrasound,fluoroscopy, and/or OCT (176), as described above. The results of theimaging study may be utilized to create a mapping representation of theneural anatomy relative to the renal artery anatomy, for example, bystimulating one or more of the associated nerve fibers and observingresulting signal conduction (178). In other words, referring back toFIGS. 14E and 14F, in one embodiment, one or more of the proximal (i.e.,closer to the aorta in the variation of FIG. 14E) circuit elementsand/or associated probing portions (element 296 of FIG. 14F) may be usedto stimulate or electrify adjacent nerve fiber (20) portions at suchproximal position, and the conduction of such stimulation may bedetected with each of the other circuit elements (294) to monitor or“map” the associated conduction pathways. The results of such mappingmay be utilized in the selective denervation of portions of the renalplexus, for example, by transmitting current to heat and denervate suchportions (180). The mapping configuration may then be utilized toconfirm that the denervation was, indeed, successful, or to what extent,with further stimulation of the pertinent fibers and monitoring of theresults. Further, renin levels, such as in the renal vein, may bemonitored to determine a level of treatment success associated with thethermal denervation treatment. Similarly, alcohol and other fluids maybe utilized and monitored for denervation. Ultimately, the pertinentinstruments may be retracted and the vascular access closed (182).

Referring to FIG. 17, a process similar to that of FIG. 16 is depicted,with the exception that a venous route is utilized to conductdenervation near the renal artery. This is believed to be lessclinically complicated in certain scenarios. The catheterinstrumentation is inserted into the inferior vena cava and navigatedtoward the renal vein (184). The renal vein is cannulated with a guideinstrument movably coupled to the sheath instrument (186). The imagingstudy is conducted not only on the neural anatomy, but also on the renalvein anatomy and renal artery anatomy to understand the relationships ofthese three and other nearby tissue structures (188). The results of theimaging study may be utilized as inputs in a mapping subprocess, whereinone or more nerve fibers may be stimulated and the resulting signalconduction observed (190). The neural anatomy map resulting from themapping efforts may be utilized for selective denervation treatment ofthe renal plexus (192), as well as in generating feedback to an operatorregarding the effectiveness of various denervation attempts (asdescribed above, renin levels also may be monitored). Subsequently theinstruments may be retracted and the vascular access closed (194).

The embodiment of FIG. 18 illustrates that process configurations suchas those described above in reference to FIGS. 16 and 17 may be broadlyapplied to many tissue structures that define one or more lumens throughwhich the pertinent instrumentation may be advanced and utilized.Referring to FIG. 18, a catheter instrument may be inserted into thetissue structure defining a lumen believed to be associated withtargeted neural tissue (252). The lumen may be cannulated with thecatheter instrument (254). An interactive imaging study may be conductedto create an image-based anatomic mapping representation of the neuralanatomy and other pertinent tissue structures (256), and an expandabledevice such as that described in reference to FIGS. 14E and 14F may beutilized to observe signal conduction (258) and create an electricalmapping which may be utilized to monitor the effectiveness of thetreatment steps (260). Subsequently the instrumentation may be removedand access to the pertinent lumens and/or tissue structures discontinued(262).

FIG. 19 illustrates aspects of an embodiment wherein arobotically-steerable catheter instrument specifically is utilized (asdescribed above, the aforementioned catheter instruments may or may notbe remotely electromechanically navigable). With the robotic catheterinstrumentation inserted into the pertinent lumen, such as an aorta inthis example (264), precision navigation and control features of therobotic instrument may be utilized during the insertional navigation(266), anatomic imaging may be conducted (268), electrical mapping maybe conducted (270), and selective denervation may be conducted (272),followed by removal of the pertinent instrumentation and closure of thevascular access (274). FIG. 21 illustrates a related embodiment with theadditional step depicted (290) of observing feedback indicators, such asrenin levels in blood exiting the renal vein and/or neural conductionparadigms with the mapping configuration, as confirming techniques formonitoring and/or adjusting treatment in a closed loop type ofconfiguration.

Referring to FIG. 20, a robotic catheter system such as that describedand incorporated above may be utilized to operate an off-the-shelftreatment head such those available on instruments from the Ardiandivision of Medtronic Corporation, to improve the navigability of suchtreatment head, and combine the treatment capabilities of such treatmenthead with additional diagnostic and treatment capabilities, such thosedescribed herein. As shown in FIG. 20, after a renal plexus denervationtreatment head has been coupled to a distal portion of a roboticcatheter instrument (276), the instrument may be inserted into an aortaor other lumen and navigated toward the renal artery or other targetedtissue structure (278). In the depicted renal intervention embodiment,the renal artery may be cannulated using the navigation control of therobotic instrumentation (280), after which an anatomic imaging study maybe conducted (282), an electrical mapping study conducted (284),selective denervation attempted with feedback from the mappingconfiguration (286), and subsequent removal of the instruments andclosure of the access (288).

Referring to FIG. 22, in another embodiment, a configuration similar tothat depicted in FIG. 14G is depicted, and in the embodiment of FIG.14G, is being operated to create a pattern of treatments (200) that issubstantially elliptical, and that is configured to reduce the chancesof post-intervention stenosis or other complications, due to the factthat the treatment contacts forming the pattern are spread over a largerlength, longitudinally, of the targeted tissue structure (here a renalartery 10). Other patterns may be created within the defined lumenspace, such as sets of curves, portions of circumferential lines, andthe like.

Referring to FIGS. 23A-23C, a configuration is illustrated wherein asubstantially helical treatment element (320) configured to conform tothe targeted lumen (here a renal artery 10 lumen) may be pushed out thedistal end of the delivery system (here a robotic sheath instrument 24),and then pulled back (322) proximally as the instrument (24) iswithdrawn proximally, creating an opportunity to cause RF electrodes orother treatment elements coupled to the helical member (320) to create alongitudinal lesion configured to denervate targeted nerve fibers (20)which may be disposed about the targeted lumen. The treatment elementscoupled to the helical member (320) may be configured or operated toremain in an “on” mode (i.e., treatment inducing; such as current flowmode with RF electrode treatment elements) during pullback (322), or maybe configured to switch on and off intermittently with various patternsover time, such patterns being pre-programmable. FIGS. 23B and 23Cillustrate further pullback (322) of the treatment assembly (24, 320),which may be automated using an “autoretract” functionality of therobotic guide/sheath catheter systems, descriptions of which areincorporated by reference herein.

Referring to FIG. 24, a set of expandable members (308, 310, such as aset of two balloons) may be used to isolate the nearby treatmentenvironment for a diagnostic/treatment configuration (292, 294) such asthat depicted in FIGS. 14D-14F. As shown in FIG. 24, a distal expandableballoon member (308), coupled to a proximal expandable balloon member(310) by a coupling member (312) that preferably defines an inflationlumen for the distal expandable balloon member (310), may be inserted ina collapsed form (not shown) through a lumen defined through the guideinstrument (24), expanded (as illustrated), and utilized to vacuum awayblood captured in the capture volume (318) for diagnostic and/ortreatment steps. With the capture volume isolated, carbon dioxide orother bioinert gases, or saline, may be infused through an infusionlumen fluidly coupled to the capture volume (318) through one or more ofthe elongate proximal instruments (24, 22, 312) to facilitate diagnosticand/or treatment steps, such as improved tissue apposition, improvedelectrical conduction, and/or improved imaging and/or visualization,such as direct visualization using an associated fiber imaging bundle orimaging chip configured to have a field of view within or adjacent tothe capture volume, or an ultrasound or OCT imaging configuration asdescribed above.

Referring to FIGS. 25A and 25B, in another embodiment, two or moreelongate steerable instruments (24, 25) may be utilized simultaneouslyfrom the same sheath instrument (23) configured to host and stabilizeboth guide instruments (24, 25) and advance a plurality of diagnosticand/or interventional probe members (298, 299). Such a sheath/guideconfiguration is described in the aforementioned incorporated byreference disclosures, and may be utilized herein to expedite andimprove upon diagnostic and treatment steps as described above. Forexample, such a configuration may be utilized to create diametricallyopposed lesions, to facilitate faster pattern creation, as described inreference to FIG. 22, and to assist with load-counterload relationshipsin delicate tissue intervention. FIG. 25B illustrates an embodimentemphasizing that the sheath instrument (23, or 24 in other depictionsherein) may be advanced distally into the renal artery or other subjecttissue structure lumen, to provide easy access for one or more guideinstruments (24, 25) to the arterioles (196) or other distal structures,which may be advantageous for direct diagnostics and interventionpertinent to the JGA cells, for example.

In another embodiment, a stent or stentlike member configured to eluteone or more drugs or compounds configured to denervate the nearbytargeted neural plexus tissue may be deployed into a structure ofinterest, such as a renal artery or renal vein, to accomplish suchdenervation over a designated period of time, after which the stent orstentlike member may be removed, resorbed, or left in place as asubstantially bioinert prosthesis.

Referring to FIGS. 26A-26C, another embodiment is illustrated wherein asteerable sheath (22) and guide instrument (24) assembly may be utilizedto provide direct access for a pre-shaped or pre-bent interventionalinstrument, such as a pre-bent J-curve instrument (352) featuring a bentelectrode portion (354) configured to create a lesion in the same shapewhen current is flowed through the electrode portion (354) and intonearby tissue structures, such as the interior of the renal artery (10),as shown, or portions of the renal vein, nearby renal nerve strands(20), JGA cells (198), and the like. In one embodiment, in a mannersimilar to that described above in reference to FIGS. 23A-23C, wherein apre-bent spiral or helical instrument (320) is pulled back through theassociated vessel, the arcuate or curved interventional instrument ofFIGS. 26A-26C may also be controllably pulled back to create an elongatelesion to disrupt the pre-existing electrical communication pathways ofthe nearby neural plexus tissue. FIGS. 26B and 26C show additionallevels of progression of pullback (350). In another embodiment, theinstrument (352) may be controllably rotated during pullback, or duringa portion of pullback, to establish a predetermined pattern of contactbetween the electrode portion (354) and the surrounding tissuestructures (10, 20, 198, 196). During pullback, current may be eithercontinuously flowed through the electrode portion (354), in which case a“long linear lesion” may be produced in a solid (i.e., noninterrupted)linear, curvy, or other pattern, or the current may be discontinuouslyflowed through the electrode portion (354), creating a “long linearlesion” may be produced in a discontinuous (i.e., interrupted) linear,curvy, or other pattern.

Referring to FIGS. 27A-27C, further details regarding aspects of ahelical or spiral type pre-bent or pre-formed instrument treatmentelement (320) may be formed and configured to behave are illustrated.Referring to FIG. 27A, a series of spiral windings (360) created on amandrel (358) may be utilized to form a helical or spiral pre-bent orpre-formed shape into a wire (356). Heat treatment may be utilized tomaintain this form for the wire (356) after removal of the mandrel, asshown in FIG. 27B, wherein the spiral wire (356) is shown coupled to apiece of metal hypotube (364) via a metallic crimpling coupler (362),which provides the wire (356) with a proximal handle or deliver memberfor operative manipulation. Referring to FIG. 27C, depending upon whatmaterials are utilized for the wire (356), it may be placed in arestraining tube or lumen (366) that radially constrains the outerdiameter of the spiral—an in such radially-collapsed configuration, theinstrument may be configured to still retain the generally spiral orhelical configuration until it is released from such constraint, afterwhich it may be configured to return to the radially expandedconfiguration, as in FIG. 27B.

Referring to FIG. 28A, in one embodiment, a J-curve type arcuateinstrument (352) may be formed by taking a J-curve-shaped insulatedguidewire, such as those available from Terumo Corporation, and removinga portion of the polymeric outer insulation, for example, with a knifeor other sharp instrument, to leave behind an exposed metallic coreportion which may be utilized as a conductive electrode portion (370),and distal (372) and proximal (368) portions which remain insulated andgenerally nonconductive relative to the conductive electrode portion(370). A farther out perspective view is shown in FIG. 28B.

Referring to FIGS. 29-34, various process embodiments are illustratedwherein one or more minimally invasive instruments may be utilized indiagnostic and/or interventional medical procedures utilizing pre-shapedinstruments as described above. Referring to FIG. 16, after a remotelysteerable sheath catheter instrument is inserted into the aorta andnavigated toward the renal artery (175), the renal artery may becannulated, for example with a coaxially associated remotely steerableguide instrument that is movably coupled to the sheath instrument (174).An interactive imaging study, or steps thereof, may be conducted of therenal artery and associated neural anatomy using one or more minimallyinvasive imaging modalities, such as ultrasound, fluoroscopy, and/or OCT(176), as described above. The results of the imaging study may beutilized to create a mapping representation of the neural anatomyrelative to the renal artery anatomy, for example, by stimulating one ormore of the associated nerve fibers and observing resulting signalconduction (178). In other words, referring back to FIGS. 14E and 14F,in one embodiment, one or more of the proximal (i.e., closer to theaorta in the variation of FIG. 14E) circuit elements and/or associatedprobing portions (element 296 of FIG. 14F) may be used to stimulate orelectrify adjacent nerve fiber (20) portions at such proximal position,and the conduction of such stimulation may be detected with each of theother circuit elements (294) to monitor or “map” the associatedconduction pathways. The results of such mapping may be utilized in theselective denervation of portions of the renal plexus using a pre-shapedinstrument such as a J-curved or spiral shaped instrument, for example,by transmitting current to heat and denervate such portions (324). Themapping configuration may then be utilized to confirm that thedenervation was, indeed, successful, or to what extent, with furtherstimulation of the pertinent fibers and monitoring of the results.Further, renin levels, such as in the renal vein, may be monitored todetermine a level of treatment success associated with the thermaldenervation treatment. Similarly, alcohol and other fluids may beutilized and monitored for denervation. Ultimately, the pertinentinstruments may be retracted and the vascular access closed (326).

Referring to FIG. 30, a process similar to that of FIG. 29 is depicted,with the exception that a venous route is utilized to conductdenervation near the renal artery. This is believed to be lessclinically complicated in certain scenarios. The catheterinstrumentation is inserted into the inferior vena cava and navigatedtoward the renal vein (184). The renal vein is cannulated with a guideinstrument movably coupled to the sheath instrument (186). The imagingstudy is conducted not only on the neural anatomy, but also on the renalvein anatomy and renal artery anatomy to understand the relationships ofthese three and other nearby tissue structures (188). The results of theimaging study may be utilized as inputs in a mapping subprocess, whereinone or more nerve fibers may be stimulated and the resulting signalconduction observed (190). The neural anatomy map resulting from themapping efforts may be utilized for selective denervation treatment ofthe renal plexus using a pre-shaped instrument, such as a j-shaped orspiral-shaped guidewire containing one or more electrodes (328), as wellas in generating feedback to an operator regarding the effectiveness ofvarious denervation attempts (as described above, renin levels also maybe monitored). Subsequently the instruments may be retracted and thevascular access closed (330).

The embodiment of FIG. 31 illustrates that process configurations suchas those described above in reference to FIGS. 29 and 30 may be broadlyapplied to many tissue structures that define one or more lumens throughwhich the pertinent instrumentation may be advanced and utilized.Referring to FIG. 31, a catheter instrument may be inserted into thetissue structure defining a lumen believed to be associated withtargeted neural tissue (252). The lumen may be cannulated with thecatheter instrument (254). An interactive imaging study may be conductedto create an image-based anatomic mapping representation of the neuralanatomy and other pertinent tissue structures (256), and an expandabledevice such as that described in reference to FIGS. 14E and 14F may beutilized to observe signal conduction (258) and create an electricalmapping which may be utilized to monitor the effectiveness of thetreatment steps with the pre-shaped instrumentation (332). Subsequentlythe instrumentation may be removed and access to the pertinent lumensand/or tissue structures discontinued (334).

FIG. 32 illustrates aspects of an embodiment wherein arobotically-steerable catheter instrument specifically is utilized (asdescribed above, the aforementioned catheter instruments may or may notbe remotely electromechanically navigable). With the robotic catheterinstrumentation inserted into the pertinent lumen, such as an aorta inthis example (264), precision navigation and control features of therobotic instrument may be utilized during the insertional navigation(266), anatomic imaging may be conducted (268), electrical mapping maybe conducted (270), and selective denervation may be conducted usingpre-shaped instruments (336), followed by removal of the pertinentinstrumentation and closure of the vascular access (338). FIG. 34illustrates a related embodiment with the additional step depicted (346)of observing feedback indicators, such as renin levels in blood exitingthe renal vein and/or neural conduction paradigms with the mappingconfiguration, as confirming techniques for monitoring and/or adjustingtreatment in a closed loop type of configuration. Steps 344 and 348 ofthe embodiment of FIG. 34 are similar to steps 336 and 338 of theembodiment of FIG. 32.

Referring to FIG. 33, a robotic catheter system such as that describedand incorporated above may be utilized to operate an off-the-shelftreatment head such as those available on instruments from the Ardiandivision of Medtronic Corporation, to improve the navigability of suchtreatment head, and combine the treatment capabilities of such treatmenthead with additional diagnostic and treatment capabilities, such thosedescribed herein. As shown in FIG. 20, after a renal plexus denervationtreatment head has been coupled to a distal portion of a roboticcatheter instrument (276), the instrument may be inserted into an aortaor other lumen and navigated toward the renal artery or other targetedtissue structure (278). In the depicted renal intervention embodiment,the renal artery may be cannulated using the navigation control of therobotic instrumentation (280), after which an anatomic imaging study maybe conducted (282), an electrical mapping study conducted (284),selective denervation attempted with feedback from the pre-shapedinstrument mapping configuration (340), and subsequent removal of theinstruments and closure of the access (342).

Any of the aforementioned deployed structures may comprise resorbablematerials in addition to the aforementioned nonresorbable materials—tofacilitate combinations and permutations which may be completelyresorbed, leaving behind a biologically healed access wound.

Further, any of the aforementioned configurations may be applied toother tissue structure configurations involving natural lumens to benavigated, and nearby neural or other tissue structures to be targeted.For example, the techniques and configurations herein may be applied toother aspects of the cardiovascular and renal/urinary systems, as wellas other anatomic subsystems including but not limited to therespiratory, upper gastric, and lower gastric subsystems.

Various exemplary embodiments of the invention are described herein.Reference is made to these examples in a non-limiting sense. They areprovided to illustrate more broadly applicable aspects of the invention.Various changes may be made to the invention described and equivalentsmay be substituted without departing from the true spirit and scope ofthe invention. In addition, many modifications may be made to adapt aparticular situation, material, composition of matter, process, processact(s) or step(s) to the objective(s), spirit or scope of the presentinvention. Further, as will be appreciated by those with skill in theart that each of the individual variations described and illustratedherein has discrete components and features which may be readilyseparated from or combined with the features of any of the other severalembodiments without departing from the scope or spirit of the presentinventions. All such modifications are intended to be within the scopeof claims associated with this disclosure.

Any of the devices described for carrying out the subject interventionsmay be provided in packaged combination for use in executing suchinterventions. These supply “kits” further may include instructions foruse and be packaged in sterile trays or containers as commonly employedfor such purposes.

The invention includes methods that may be performed using the subjectdevices. The methods may comprise the act of providing such a suitabledevice. Such provision may be performed by the end user. In other words,the “providing” act merely requires the end user obtain, access,approach, position, set-up, activate, power-up or otherwise act toprovide the requisite device in the subject method. Methods recitedherein may be carried out in any order of the recited events which islogically possible, as well as in the recited order of events.

Exemplary aspects of the invention, together with details regardingmaterial selection and manufacture have been set forth above. As forother details of the present invention, these may be appreciated inconnection with the above-referenced patents and publications as well asgenerally known or appreciated by those with skill in the art. Forexample, one with skill in the art will appreciate that one or morelubricious coatings (e.g., hydrophilic polymers such aspolyvinylpyrrolidone-based compositions, fluoropolymers such astetrafluoroethylene, hydrophilic gel or silicones) may be used inconnection with various portions of the devices, such as relativelylarge interfacial surfaces of movably coupled parts, if desired, forexample, to facilitate low friction manipulation or advancement of suchobjects relative to other portions of the instrumentation or nearbytissue structures. The same may hold true with respect to method-basedaspects of the invention in terms of additional acts as commonly orlogically employed.

In addition, though the invention has been described in reference toseveral examples optionally incorporating various features, theinvention is not to be limited to that which is described or indicatedas contemplated with respect to each variation of the invention. Variouschanges may be made to the invention described and equivalents (whetherrecited herein or not included for the sake of some brevity) may besubstituted without departing from the true spirit and scope of theinvention. In addition, where a range of values is provided, it isunderstood that every intervening value, between the upper and lowerlimit of that range and any other stated or intervening value in thatstated range, is encompassed within the invention.

Also, it is contemplated that any optional feature of the inventivevariations described may be set forth and claimed independently, or incombination with any one or more of the features described herein.Reference to a singular item, includes the possibility that there areplural of the same items present. More specifically, as used herein andin claims associated hereto, the singular forms “a,” “an,” “said,” and“the” include plural referents unless the specifically stated otherwise.In other words, use of the articles allow for “at least one” of thesubject item in the description above as well as claims associated withthis disclosure. It is further noted that such claims may be drafted toexclude any optional element. As such, this statement is intended toserve as antecedent basis for use of such exclusive terminology as“solely,” “only” and the like in connection with the recitation of claimelements, or use of a “negative” limitation.

Without the use of such exclusive terminology, the term “comprising” inclaims associated with this disclosure shall allow for the inclusion ofany additional element—irrespective of whether a given number ofelements are enumerated in such claims, or the addition of a featurecould be regarded as transforming the nature of an element set forth insuch claims. Except as specifically defined herein, all technical andscientific terms used herein are to be given as broad a commonlyunderstood meaning as possible while maintaining claim validity.

The breadth of the present invention is not to be limited to theexamples provided and/or the subject specification, but rather only bythe scope of claim language associated with this disclosure.

The invention claimed is:
 1. A method for ablating a nerve adjacent arenal artery, the method comprising: navigating a pre-shaped ablativeelement positioned at or near a distal end of a flexible, robotic,electromechanically steerable catheter into the renal artery in acollapsed configuration, using one or more control elements coupled to aproximal end of the steerable catheter; imaging targeted portions of thenerve from inside the renal artery to create an anatomic map of thetargeted portions; using the anatomical map to create thereon anelectrical map of the targeted portions relative to the renal artery, toassist in identification of selective denervation treatment locationswithin a renal plexus adjacent the renal artery; causing the pre-shapedablative element to assume an expanded configuration within the renalartery to contact an inner wall of the renal artery in a patternconfigured to address the targeted portions, based at least in part onthe anatomic map and the electrical map; passing a current through thepre-shaped ablative element to ablate the nerve; and monitoring progressof ablation of the nerve, using the pre-shaped ablative element and theelectrical map.
 2. The method of claim 1, wherein the steerable cathetercomprises a coaxially-associated catheter configured to move in responseto control signals from a master input device configured to be manuallyoperated by an operator.
 3. The method of claim 1, wherein creating anelectrical map comprises: stimulating a first portion of the nerve; anddetecting conduction of the stimulation at a second portion of the nervelongitudinally displaced from the first portion.
 4. The method of claim3, further comprising associating a first nerve anatomical location withthe first portion of the nerve and a second nerve anatomical locationwith the second portion of the nerve.
 5. The method of claim 4, furthercomprising associating a renal artery anatomical location from theanatomic map with each of the nerve anatomical locations to form anelectroanatomical map.
 6. The method of claim 1, wherein the treatmentpre-shaped ablative element comprises a radiofrequency electrode, andwherein passing the current through the ablative element comprisespassing current through the electrode.
 7. The method of claim 1, furthercomprising advancing the pre-shaped ablative element relative to thedistal portion of the steerable catheter.
 8. The method of claim 1,wherein creating an electrical map comprises stimulating a first portionof the nerve and detecting conduction of the stimulation in a portion ofa neural plexus associated with the nerve.
 9. The method of claim 1,further comprising moving the pre-shaped ablative element relative tothe targeted portions while passing current through the pre-shapedablative element to ablate an elongate portion of the nerve.
 10. Themethod of claim 9, wherein the moving is actuated by manual orelectromechanical pullback of the pre-shaped ablative element.